import numpy as np
arr1 = np.zeros(2)
print('一堆数组arr1:\n',arr1)
arr2 = np.zeros((2,3))
print('二维数组arr2:\n',arr2)
arr3 = np.ones(3)
print('一位数组arr3:\n',arr3)
arr4 = np.ones((3,3))
print('二维数组arr4:\n',arr4)
arr5 = np.empty(4)
print('一位数组arr5:\n',arr5)
arr6 = np.empty((3,4),dtype='int')
print('二维整形数组arr6:\n',arr6)